GRAND ORGUE

Exploded drawing

Assembly

Although the GRAND ORGUE cabinet consists of many individual parts, it is, in fact, easy to build because all the parts have only 90° angles and there are no bevels required. The cabinet consists of two halves which are held together by 16 threaded rods after the drivers have been fitted. The split construction is necessary because it would not be possible to fit the woofers inside a closed cabinet. To ensure the two halves are properly positioned relative to each other, we recommend wooden plugs or a similar locating system.

Initially, the construction of the two halves is identical. Glue the outer spacers and rear wall to the outer wall which has the cutout in it for the magnets. To this, glue the inner wall with the large cutouts for the woofer baskets. This completes part 2 of the cabinet. On part 1, we now glue the baffle and the rear wall for the full-range drivers in place and attach the inner spacers, which completes this part. If you intend to fit the full-rangedrivers from the back, as originally planned, we recommend you use screw-in nuts. These have to be screwed in before the baffle is glued in place because, afterwards, it is hardly possible to access them. Fitting the drivers from behind is mainly for appearance's sake. If you do not feel up to milling the oval cutouts exactly, you can also fit the drivers from the outside. In this case, however, we would recommend you fit a grille frame with acoustic fabric because the SL 713's basket is not particularly attractive.

It is also necessary to drill holes in the outer spacers, preferably before gluing together, to pass the wires through. The four woofers in each half of the cabinet are soldered in parallel, and these two groups then connected in series. This involves laying connecting wires between the enclosures and a connection from one of the halves to the other. For the full-range drivers, it is only necessary to drill a hole in the rear wall of the full-range enclosure.

Since there is no room inside the cabinet for the crossover, it has to be placed outside. There are no limits to your imagination. You could make a wooden base for the speaker and hide it there or just use a wooden board and mount it on that so that it is visible. There is also hardly room for terminal connections, so you will need to improvise here, too. The gold-plated screw terminals on the BT 95/75 (or from the HIGH-END-TERMINAL) can be unscrewed and fitted in the rear wall, which is an attractive solution in connection with the wood panelling. Alternatively, the wires can be fed straight from the driver to the crossover without an intermediate terminal.

To reduce the wiring to a minimum, the series capacitors (Elko Special 100 µF and MKT 47 µF), which are responsible for splitting the BB array (see above), can be housed in the full-range enclosure. They can be soldered onto the appropriate driver direct with short pieces of wire and placed in the bottom of the enclosure. Experience has shown that it makes sense to solder up all the eight full-range drivers including the series crossover while they are outside the cabinet and then to position the drivers and wiring in the cabinet afterwards. Soldering the wires on with the drivers already fitted would be far more complicated than outside the cabinet side by side on the table.

HINT: After the whole construction has been glued together, tie the two halves firmly using the threaded rods but before you fit the drivers. At this stage it is possible to sand off any irregularities using an orbital sander so that the two halves match perfectly.

Inner damping

Fold two mats of damping material longways for each of the full-rangeparts of the cabinet and push them inside. No damping is required in the woofer enclosures.